RESUMO

Placental development is particularly altered in trisomy of chromosome 21 (T21)-affected pregnancies. We previously described in T21-affected placentae an abnormal paracrine crosstalk between the villus mesenchymal core and villus trophoblasts. T21-affected placentae are known to be characterized by their hypovascularity. However, the causes of this anomaly remain not fully elucidated. Therefore, the hypothesis of an abnormal paracrine crosstalk between fetal mesenchymal core and placental endothelial cells (PLECs) was evocated. Villus mesenchymal cells from control (CMCs) and T21 placentae (T21MCs) were isolated and grown in culture to allow their characterization and collection of conditioned media for functional analyses (CMC-CM and T21MC-CM, respectively). Interestingly, PLEC proliferation and branching ability were less stimulated by T21MC-CM than by CMC-CM. Protein array analysis identified secreted proangiogenic growth factors in CMC-CM, which were reduced in T21MC-CM. Combined mass spectrometry and biochemical analysis identified spondin-2 as a factor decreased in T21MC-CM compared with CMC-CM. We found that exogenous spondin-2 stimulated PLEC proliferation and established that T21MC-CM supplemented with spondin-2 recovered conditioned media ability to induce PLEC proliferation and angiogenesis. Hence, this study demonstrates a crosstalk between villus mesenchymal and fetal endothelial cells, in which spondin-2 secreted from mesenchymal cells plays a central role in placental vascular functions. Furthermore, our results also suggest that a reduction in spondin-2 secretion may contribute to the pathogenesis of T21 placental hypovascularity.

RESUMO

Bardet-Biedl syndrome (BBS) is an emblematic ciliopathy associated with retinal dystrophy, obesity, postaxial polydactyly, learning disabilities, hypogonadism and renal dysfunction. Before birth, enlarged/cystic kidneys as well as polydactyly are the hallmark signs of BBS to consider in absence of familial history. However, these findings are not specific to BBS, raising the problem of differential diagnoses and prognosis. Molecular diagnosis during pregnancies remains a timely challenge for this heterogeneous disease (22 known genes). We report here the largest cohort of BBS fetuses to better characterize the antenatal presentation. Prenatal ultrasound (US) and/or autopsy data from 74 fetuses with putative BBS diagnosis were collected out of which molecular diagnosis was established in 51 cases, mainly in BBS genes (45 cases) following the classical gene distribution, but also in other ciliopathy genes (6 cases). Based on this, an updated diagnostic decision tree is proposed. No genotype/phenotype correlation could be established but postaxial polydactyly (82%) and renal cysts (78%) were the most prevalent symptoms. However, autopsy revealed polydactyly that was missed by prenatal US in 55% of the cases. Polydactyly must be carefully looked for in pregnancies with apparently isolated renal anomalies in fetuses.

RESUMO

BACKGROUND/AIMS: This study aims to describe the autonomic nervous network of the female pelvis with a 3D model and to provide a safe plane of dissection during radical hysterectomy for cervical cancer. METHODS: Pelvises of 3 human female fetuses were studied by using the computer-assisted anatomic dissection. RESULTS: The superior hypogastric plexus (SHP) was located at the level of the aortic bifurcation in front of the sacral promontory and divided inferiorly and laterally into 2 hypogastric nerves (HN). HN ran postero-medially to the ureter and in the lateral part of the uterosacral ligament until the superior angle of the inferior hypogastric plexus (IHP). IHP extended from the anterolateral face of the rectum, laterally to the cervix and attempted to the base of the bladder. Vesical efferences merged from the crossing point of the ureter and the uterine artery and ran through the posterior layer of the vesico-uterine ligament. CONCLUSIONS: The SHP could be injured during paraaortic lymphadenectomy. Following the ureter and resecting the medial fibrous part of the uterosacral ligament may spare the HN. No dissection should be performed under the crossing point of the ureter and the uterine artery.

RESUMO

Fanconi anemia (FA) causes bone marrow failure early during childhood, and recent studies indicate that a hematopoietic defect could begin in utero. We performed a unique kinetics study of hematopoiesis in Fancg-/- mouse embryos, between the early embryonic day 11.5 (E11.5) to E12.5 developmental window (when the highest level of hematopoietic stem cells [HSC] amplification takes place) and E14.5. This study reveals a deep HSC defect with exhaustion of proliferative and self-renewal capacities very early during development, together with severe FA clinical and biological manifestations, which are mitigated at E14.5 due to compensatory mechanisms that help to ensure survival of Fancg-/- embryos. It also reports that a deep HSC defect is also observed during human FA development, and that human FA fetal liver (FL) HSCs present a transcriptome profile similar to that of mouse E12.5 Fancg-/- FL HSCs. Altogether, our results highlight that early mouse FL could represent a good alternative model for studying Fanconi pathology.

RESUMO

Trisomy 13 or Patau syndrome (PS) is a well-known aneuploidy characterized by a polymalformative syndrome. We described a large series of fetuses with PS and compared them with cases described in the literature, most of which were live-born. In all, 42 fetuses, aged from 14 to 41 gestational weeks (GW), were examined. The main defects observed were similar to those described in live-born patients: congenital heart defects (76%), holoprosencephaly spectrum anomalies including arhinencephaly and hypotelorism (74%), urinary tract anomalies (71%), ear anomalies (69%), postaxial polydactyly (67%), anogenital anomalies (60%), anophthalmos, and/or microphthalmos (53%), brachycephaly (45%), and oro-facial clefts (45%). A duplication or triplication of at least one distal phalanx of the thumb or hallux was present in 38% of fetuses. This sign has only been reported previously in one patient in the literature. Fetal examination in trisomy 13, is thus, useful to complete the phenotype or to orient diagnosis toward trisomy 13 in the absence of cytogenetic analysis.

RESUMO

EFEMP2 mutations are known to be responsible for autosomal recessive cutis laxa type 1B (ARCL1B), a rare multisystem disease affecting skin, skeleton, and vascular structures. We report 2 additional related cases of ARCL1B of particular severity leading to termination of pregnancy. Cardinal signs of this connective tissue disease were already seen during the second trimester of pregnancy, then confirmed and clarified at autopsy. Anomalies included cutis laxa, arachnodactyly, clubfoot, wormian bones, moderate bowing of long bones with slender bone trabeculae, rib fractures, undermuscularized diaphragm, hiatal hernia, and arterial tortuosity with thick vascular walls and disorganized elastic fibers. Sequencing of the EFEMP2 gene revealed a novel homozygous nonsense mutation: c.639C>A (p.Cys213*). We performed a thorough histological analysis and discuss differential diagnoses, genotype-phenotype correlations, and the challenge of prenatal diagnosis of this disease.

RESUMO

The estimated prevalence of fetal caudal dysgenesis is 1 per 100,000 births. The functional prognosis of sacral agenesis is dominated by the large spectrum of associated caudal malformations. Except for cases associated with hydrocephalus secondary to open spinal dysraphism or chromosomal anomalies, association with mental deficiency is rare. We propose a systematic prenatal approach to cases of fetal sacral agenesis based on 9 etiologic items: clinical context, type of sacral dysgenesis, associated spinal cord malformations, mobility of lower limbs, investigation of the presacral region, analysis of the gastrointestinal tract, analysis of the genitourinary tract, associated vertebral defects, and cytogenetic analysis.

RESUMO

OBJECTIVES: To investigate the relationship between histologic findings of the placenta and response to early postnatal hydrocortisone treatment used to prevent bronchopulmonary dysplasia (BPD) in extremely preterm infants. METHODS: In an exploratory analysis of the Early Low-Dose Hydrocortisone to Improve Survival Without Bronchopulmonary Dysplasia in Extremely Preterm Infants (PREMILOC) trial, detailed placental analyses were performed on the basis of standardized macroscopic and histologic examinations. Placental histology, categorized into 3 groups, was correlated to neonatal outcomes and response to hydrocortisone treatment. RESULTS: Of 523 randomly assigned patients, 457 placentas were analyzed. In total, 125 out of 457 (27%) placentas were classified as normal, 236 out of 457 (52%) placentas were classified as inflammatory, and 96 out of 457 (21%) placentas were classified as vascular. Placental inflammation was associated with a significant, increased rate of BPD-free survival at 36 weeks' postmenstrual age, independent of gestational age, treatment group, and sex (adjusted odds ratio: 1.72, 95% confidence interval [CI]: 1.05 to 2.82, P = .03). Regarding the response to treatment, the strongest benefit of hydrocortisone compared with placebo was found in infants born after placental vascular disease, with significantly more patients extubated at day 10 (risk difference: 0.32, 95% CI: 0.08 to 0.56, P = .004) and similar positive direction on survival without BPD (risk difference: 0.23, 95% CI: 0.00 to 0.46, P = .06). Adjusted to gestational age and treatment groups, placental inflammation was associated with significantly fewer patent ductus arteriosus ligation (adjusted hazard ratio: 0.58, 95% CI: 0.36 to 0.95, P = .03). Placental histology was not found to be associated with other adverse events related to preterm birth. CONCLUSIONS: With these findings, we confirm that early low-dose hydrocortisone confers benefits in extremely preterm infants overall and we suggest there is a higher treatment effect in those born after placental vascular disease.

RESUMO

INTRODUCTION: Ablation of the acardiac twin umbilical cord in the TRAP protects the normal donor twin. MATERIALS AND METHODS: Two case descriptions, one of interstitial laser photocoagulation and one of laser umbilical cord occlusion (L-UCO) of the acardiac twin in monochorionic monoamniotic pregnancies are reported. RESULTS: L-UCO in two pregnancies with TRAP syndrome in the second trimester resulted in intrauterine fetal death in both cases after 1 month. Case 1 had no detectable cause of fetal death. Case 2 had rupture of the amniotic sac causing anhydramnios and acute chorioamnionitis. A groove on the umbilical cord of the normal twin indicated a cord stricture due to cord entanglement. CONCLUSION: Our experience confirms that the best timing and optimal treatment of MC/MA twins complicated by TRAP sequence still remains a controversial clinical issue. Cord entanglement may continue be a potential clinical risk factor for adverse perinatal outcome even after ablation therapy.

RESUMO

The classical model of hematopoiesis established in the mouse postulates that lymphoid cells originate from a founder population of common lymphoid progenitors. Here, using a modeling approach in humanized mice, we showed that human lymphoid development stemmed from distinct populations of CD127- and CD127+ early lymphoid progenitors (ELPs). Combining molecular analyses with in vitro and in vivo functional assays, we demonstrated that CD127- and CD127+ ELPs emerged independently from lympho-mono-dendritic progenitors, responded differently to Notch1 signals, underwent divergent modes of lineage restriction, and displayed both common and specific differentiation potentials. Whereas CD127- ELPs comprised precursors of T cells, marginal zone B cells, and natural killer (NK) and innate lymphoid cells (ILCs), CD127+ ELPs supported production of all NK cell, ILC, and B cell populations but lacked T potential. On the basis of these results, we propose a "two-family" model of human lymphoid development that differs from the prevailing model of hematopoiesis.

RESUMO

Interstitial 2p15p16.1 microdeletion is a rare chromosomal syndrome previously reported in 33 patients. It is characterized by intellectual disability, developmental delay, autism spectrum disorders, microcephaly, short stature, dysmorphic features, and multiple congenital organ defects. It is defined as a contiguous gene syndrome and two critical regions have been proposed at 2p15 and 2p16.1 loci. Nevertheless, patients with deletion of both critical regions shared similar features of the phenotype and the correlation genotype-phenotype is still unclear. We review all published cases and describe three additional patients, to define the phenotype-genotype correlation more precisely. We reported on two patients including the first prenatal case described so far, carrying a 2p15 deletion affecting two genes: XPO1 and part of USP34. Both patients shared similar features including facial dysmorphism and cerebral abnormalities. We considered the genes involved in the deleted segment to further understand the abnormal phenotype. The third case we described here was a 4-year-old boy with a heterozygous de novo 427 kb deletion encompassing BCL11A and PAPOLG at 2p16.1. He displayed speech delay, autistic traits, and motor stereotypies associated with brain structure abnormalities. We discuss the contribution of the genes included in the deletion to the abnormal phenotype. Our three new patients compared to previous cases, highlighted that despite two critical regions, both distal deletion at 2p16.1 and proximal deletion at 2p15 are associated with phenotypes that are very close to each other. Finally, we also discuss the genetic counseling of this microdeletion syndrome particularly in the course of prenatal diagnosis.

RESUMO

Congenital hydrocephalus is considered as either acquired due to haemorrhage, infection or neoplasia or as of developmental nature and is divided into two subgroups, communicating and obstructive. Congenital hydrocephalus is either syndromic or non-syndromic, and in the latter no cause is found in more than half of the patients. In patients with isolated hydrocephalus, L1CAM mutations represent the most common aetiology. More recently, a founder mutation has also been reported in the MPDZ gene in foetuses presenting massive hydrocephalus, but the neuropathology remains unknown. We describe here three novel homozygous null mutations in the MPDZ gene in foetuses whose post-mortem examination has revealed a homogeneous phenotype characterized by multiple ependymal malformations along the aqueduct of Sylvius, the third and fourth ventricles as well as the central canal of the medulla, consisting in multifocal rosettes with immature cell accumulation in the vicinity of ependymal lining early detached from the ventricular zone. MPDZ also named MUPP1 is an essential component of tight junctions which are expressed from early brain development in the choroid plexuses and ependyma. Alterations in the formation of tight junctions within the ependyma very likely account for the lesions observed and highlight for the first time that primary multifocal ependymal malformations of the ventricular system is genetically determined in humans. Therefore, MPDZ sequencing should be performed when neuropathological examination reveals multifocal ependymal rosette formation within the aqueduct of Sylvius, of the third and fourth ventricles and of the central canal of the medulla.

RESUMO

BACKGROUND: There is no precise prenatal indicator to refine an accurate prognosis in case of sacral agenesis and to define the diagnostic approach and outcome criteria in case of fetal sacral agenesis using 3 characteristics of the conus medullaris (CM): its position, its appearance, and associated spinal abnormalities. METHODS: Ten cases of prenatally diagnosed sacral agenesis were included between 1995 and 2014 after collating ultrasound findings and prenatal computed tomography data. RESULTS: Two cases of total sacral agenesis and 8 of partial agenesis were included. There were 1 or more spinal abnormalities in 8/10 cases: 6 lipomas, 4 low-lying tethered cords, 2 diastematomyelias, and 1 syringomyelia. Three situations were distinguished: sacral agenesis with low-lying tethered cord, sacral agenesis with a truncated CM, and sacral agenesis with CM in place. If the sacral agenesis is isolated, a lipoma should be sought. Lipomas of the filum have a good prognosis, whereas lipomas of the CM cause neurological deficits in 1/3 of cases. When there is a low-lying tethered cord, a diastematomyelia or a syringomyelia may be associated. In truncated CM, there may be a severe form suggestive of caudal regression syndrome. Serious ultrasound signs are immobility of the lower limbs, talipes equinovarus, impaired bladder emptying, and dilatation of the upper urinary tract. CONCLUSION: A precise description of the morphology of the CM, its position, and associated spinal malformations are important in defining the neurological, urinary, gastrointestinal, and motor functions prognosis in cases of fetal sacral agenesis.

RESUMO

The molecular mechanisms that orchestrate the development of the human dentate gyrus are not known. In this study, we characterized the formation of human dentate and fimbrial progenitors and postmitotic neurons from 9 gestational weeks (GW9) to GW25. PAX6+ progenitor cells remained proliferative until GW16 in the dentate ventricular zone. By GW11, the secondary dentate matrix had developed in the intermediate zone, surrounding the dentate anlage and streaming toward the subpial layer. This secondary matrix contained proliferating PAX6+ and/or TBR2+ progenitors. In parallel, SOX2+ and PAX6+ fimbrial cells were detected approaching the dentate anlage, representing a possible source of extra-dentate progenitors. By GW16, when the granule cell layer could be delineated, a hilar matrix containing PAX6+ and some TBR2+ progenitors had become identifiable. By GW25, when the 2 limbs of the granule cell layer had formed, the secondary dentate matrix was reduced to a pool of progenitors at the fimbrio-dentate junction. Although human dentate development recapitulates key steps previously described in rodents, differences seemed to emerge in neuron layer markers expression. Further studies are necessary to better elucidate their role in dentate formation and connectivity.

RESUMO

Arthrogryposis multiplex congenita (AMC) is a developmental condition characterized by multiple joint contractures resulting from reduced or absent fetal movements. Through linkage analysis, homozygosity mapping, and exome sequencing in four unrelated families affected by lethal AMC, we identified biallelic mutations in GLDN in the affected individuals. GLDN encodes gliomedin, a secreted cell adhesion molecule involved in the formation of the nodes of Ranvier. Transmission electron microscopy of the sciatic nerve from one of the affected individuals showed a marked lengthening defect of the nodes. The GLDN mutations found in the affected individuals abolish the cell surface localization of gliomedin and its interaction with its axonal partner, neurofascin-186 (NF186), in a cell-based assay. The axoglial contact between gliomedin and NF186 is essential for the initial clustering of Na+ channels at developing nodes. These results indicate a major role of gliomedin in node formation and the development of the peripheral nervous system in humans. These data indicate that mutations of GLDN or CNTNAP1 (MIM: 616286), encoding essential components of the nodes of Ranvier and paranodes, respectively, lead to inherited nodopathies, a distinct disease entity among peripheral neuropathies.

RESUMO

Ciprofloxacin, a broad-spectrum antimicrobial agent belonging to the fluoroquinolone family, is prescribed off-label in infants less than one year of age. Ciprofloxacin is included in the European Medicines Agency priority list of off-patent medicinal products requiring evaluation in neonates. This evaluation is undergoing within the TINN (Treat Infections in Neonates) FP7 EU project. As part of the TINN project, the present preclinical study was designed to assess the potential adverse effects of Ciprofloxacin on neurodevelopment, liver and joints in mice. Newborn mice received subcutaneous Ciprofloxacin at 10, 30 and 100 mg/kg/day from 2 to 12 postnatal days. Peak plasma levels of Ciprofloxacin were in the range of levels measured in human neonates. We examined vital functions in vivo, including cardiorespiratory parameters and temperature, psychomotor development, exploratory behavior, arthro-, nephro- and hepato-toxic effects. We found no effect of Ciprofloxacin at 10 and 30 mg/kg/day. In contrast, administration at 100 mg/kg/day delayed weight gain, impaired cardiorespiratory and psychomotor development, caused inflammatory infiltrates in the connective tissues surrounding the knee joint, and moderately increased extramedullary hematopoiesis. The present study pleads for careful watching of cardiorespiratory and motor development in neonates treated with Ciprofloxacin, in addition to the standard surveillance of arthrotoxicity.

RESUMO

The molecular mechanisms underlying the formation of hippocampus are unknown in humans. To improve our knowledge of molecules that potentially regulate pyramidal neurogenesis and layering in various hippocampal fields, we investigated the expression of progenitor markers and cell fate molecules from gestational week (GW) 9 to GW 20. At GW 9, the progenitor cell compartment of the hippocampal formation mainly consisted of PAX6(+) cells in the ventricular zone. Between GW 9 and 11, a second germinal area, the subventricular zone (SVZ), was formed, as shown by TBR2 labeling. Postmitotic markers (TBR1, CTIP2, SATB2, and CUX1) might reflect the inside-out layering of the plate from GW 11 onwards. TBR1(+) neurons appeared in the deep plate, whereas CTIP2(+), SATB2(+), and CUX1(+) neurons occupied the upper layers. From GW 16, differences in layer segregation were observed between the ammonic and subicular plates. Moreover, an ammonic-to-subicular maturation gradient was observed in germinal/postmitotic areas. Taken together, these findings demonstrate for the first time the presence of an SVZ in the hippocampus of human fetuses and laminar differences in transcription factor expression in the pyramidal layer of the human ammonic and subicular plate, and provide new information to further investigate the connectivity of the hippocampal formation.

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